longitudinal and sound waves demonstrated and explained

In this video I look at what longitudinal waves are, demonstrating them using a slinky. I demonstrate that a longitudinal wave requires a medium, using a speaker in a vacuum jar.
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[@vipulsharma6241]

Thanks for clearing long pending doubts, things becomes easier to understand with live examples.

[@yasmineamer1933]

oh my god thank you so much, this is helping me get a wonderful foundation for my physics report

[@prateeksharma6756]

Amazing video sir.. i think you are one of the few teachers that i have found on the internet who actually have deep understanding of the concept they are talking about...

[@PhysicsHigh]

Thanks

[@mogusgod5954]

very nice demonstration there very much helps the understanding great video thanks dood

[@darshmehta6666]

I'm watching this for my physics class lmao. Thanks for explaining thoo pretty informative video:)

[@laurajevans6415]

me just watching this for my homework 😅

[@jacksparow2132]

please keep this up man you are really great!!!

[@nanaputuu2596]

Very good presentation,sir.....my regards

[@Greg_Chase]

If the medium is modified (the 'medium' being the air, the molecules that make up our atmosphere), the sound waves' ability to travel is affected. For example, in a vacuum chamber with all the air molecules removed, only the encasement (metal, thick glass, etc.) can propagate sound waves. In a natural vacuum like in space, there is next to nothing able to transmit sound. So for the propagation of sound waves, we need the medium - we need a large collection of molecules in a fairly uniform distribution to allow the propagation/transmission of sound waves from the source to a destination, such as from one person to another. A small team of us work at using electromagnetic effects on the charged particles in metal surfaces to create very moderate-strength artificial gravity. We use a dielectric barrier discharge-related system to pre-polarize the charged particles in the metal, then apply a strong, static magnetic field orthogonal (at a right angle) to the metal, and then induce very high (microwave) frequency eddy currents in, and parallel with, the metal plating of the hull of the device. The 90 degree angle between the magnetic field and the induced microwave RF (radio frequency) eddy currents oscillating in the metal, manifests the Lorentz force, which deflects (accelerates) the charged particles in the metal, at a very high rate of back-and-forth acceleration (aka oscillations). The accelerations of the pre-polarized charged particles are uniform/coherent due to the way the Lorentz force works. The very mild-strength artificial gravity field created in the immediate surrounding of the metal plating restricts (attracts) the nearby air molecules, and the sound made by the process (known as 'Barkhausen noise') created by the rapid shifts in the magnetic polarization of the charged particles in the metal cannot be heard if you stand a few feet from the test device. The artificial gravity field creates a concentration of air molecules at the metal plates - when sound waves from the Barkhausen noise exit the metal and hit the condensed air molecules, they do not propagate outside the thin layer of concentrated air around the hull - the air molecules that would normally permit the passage of air waves has a discontinuity that attenuates the sound greatly. We have not yet been able to measure the thickness of the layer of condensed air but it is dictated by the strength of the artificial gravity field created by the metal plating. Light waves can also be affected by the medium: light waves passing through a denser medium than air (for example, water) have their path altered. For waves in general, the medium - and alteration of the medium - play a huge role in how/if waves propagate. Thank you for you excellent video!

[@hasha9320]

Wonder why my teacher chose this video your special great video 👍🏽

[@belindakileghe2694]

wow.... Its amazing sir😀

[@rituvardani333]

When we do vibrate a slinky it goes with some compression.Now is that always true that's the wave should come back too with same energy. Energy is conserved right??

[@naveensundar4765]

nice!

[@zulmastevens8225]

If sounds travels faster through medium why is it that radio waves are deterred by trees or mountains? Is it because they are different types of waves?

[@therealsan9949]

awesome

[@JongJande]

Speed of sound c_krit = 91.2 * SQRT(kappa*T_abs/MW) .... which says that the speed of sound in independent of the pressure of the medium, but is dependent on the temperature of the medium.

[@raymondblake5765]

So you can think of sound as a sine wave traveling through a medium. Now say you have a particle whose equilibrium position is at point x. If the sound wave travels through point x Let's say at time t, and the value of the wave at point x is 3, then is the position of the particle at time t equal to x(t)= x +3 ? If this is how it works, how do we show that the wave relates to the idea of a moving region of compression? And finally, a moving 'pressure'?

[@prateeksharma6756]

You cannot think of the particle as a sine wave travelling through a medium... The particles of a wave are doing harmonic motion... They are basically vibrating at one place... It's like a point the guitar string, it vibrates(back and forth motion) but it does not travel...

[@greymatter4096]

Epic

[@sherwazir889]

We need your help in physics to clearour concept

[@cwj9202]

At @ 2:00, wouldn't that be similar to an echo?

[@meganpage5665]

sir are you south african? i know you're australian (or kiwi) but like you have an undertone of a south african accent.

[@PhysicsHigh]

Close. I am actually Dutch by birth. Though I was 8 when I came to Australia

[@meganpage5665]

@@PhysicsHigh ahhhh, the dutch makes sense. i'm south african and it sounds alot like the afrikaans accent.

[@mindbendersambition7014]

Sup 8A